merges r30629 and r30630 from trunk into ruby_1_9_2.

--
* ext/psych/lib/psych/visitors/to_ruby.rb: merge keys are actually
  part of YAML 1.1, so they should be supported.  Remove warning and
  merge keys to parent.  [ruby-core:34679]
* test/psych/test_merge_keys.rb: test for merge keys
--
* ext/psych/lib/psych/visitors/to_ruby.rb: fixing merge key support
  when multiple merge keys are specified.
* test/psych/test_merge_keys.rb: tests for multi-merge key support

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_2@31856 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

4 files changed, 98 insertions, 8 deletions

diff --git a/ChangeLog b/ChangeLog
index 25431da2c5..d5e1728b61 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,18 @@
+Sat Jan 22 11:49:55 2011  Aaron Patterson <aaron@tenderlovemaking.com>
+
+	* ext/psych/lib/psych/visitors/to_ruby.rb: fixing merge key support
+	  when multiple merge keys are specified.
+
+	* test/psych/test_merge_keys.rb: tests for multi-merge key support
+	
+Sat Jan 22 11:33:04 2011  Aaron Patterson <aaron@tenderlovemaking.com>
+
+	* ext/psych/lib/psych/visitors/to_ruby.rb: merge keys are actually
+	  part of YAML 1.1, so they should be supported.  Remove warning and
+	  merge keys to parent.  [ruby-core:34679]
+
+	* test/psych/test_merge_keys.rb: test for merge keys
+
 Thu Jul 15 00:35:09 2010  Tanaka Akira  <akr@fsij.org>
 
 	* time.c (localtime_with_gmtoff_zone): renamed from
diff --git a/ext/psych/lib/psych/visitors/to_ruby.rb b/ext/psych/lib/psych/visitors/to_ruby.rb
index f3441fff92..a68c8e698e 100644
--- a/ext/psych/lib/psych/visitors/to_ruby.rb
+++ b/ext/psych/lib/psych/visitors/to_ruby.rb
@@ -190,14 +190,17 @@ module Psych
           o.children.each_slice(2) { |k,v|
             key = accept(k)
 
-            if key == '<<' && Nodes::Alias === v
-              # FIXME: remove this when "<<" syntax is deprecated
-              if $VERBOSE
-                where = caller.find { |x| x !~ /psych/ }
-                warn where
-                warn "\"<<: *#{v.anchor}\" is no longer supported, please switch to \"*#{v.anchor}\""
+            if key == '<<'
+              case v
+              when Nodes::Alias
+                hash.merge! accept(v)
+              when Nodes::Sequence
+                accept(v).reverse_each do |value|
+                  hash.merge! value
+                end
+              else
+                hash[key] = accept(v)
               end
-              return accept(v)
             else
               hash[key] = accept(v)
             end
diff --git a/test/psych/test_merge_keys.rb b/test/psych/test_merge_keys.rb
new file mode 100644
index 0000000000..fef8892727
--- /dev/null
+++ b/test/psych/test_merge_keys.rb
@@ -0,0 +1,72 @@
+require_relative 'helper'
+
+module Psych
+  class TestMergeKeys < TestCase
+    # [ruby-core:34679]
+    def test_merge_key
+      yaml = <<-eoyml
+foo: &foo
+  hello: world
+bar:
+  << : *foo
+  baz: boo
+      eoyml
+
+      hash = {
+        "foo" => { "hello" => "world"},
+        "bar" => { "hello" => "world", "baz" => "boo" } }
+      assert_equal hash, Psych.load(yaml)
+    end
+
+    def test_multiple_maps
+      yaml = <<-eoyaml
+---
+- &CENTER { x: 1, y: 2 }
+- &LEFT { x: 0, y: 2 }
+- &BIG { r: 10 }
+- &SMALL { r: 1 }
+
+# All the following maps are equal:
+
+- # Merge multiple maps
+  << : [ *CENTER, *BIG ]
+  label: center/big
+      eoyaml
+
+      hash = {
+        'x' => 1,
+        'y' => 2,
+        'r' => 10,
+        'label' => 'center/big'
+      }
+
+      assert_equal hash, Psych.load(yaml)[4]
+    end
+
+    def test_override
+      yaml = <<-eoyaml
+---
+- &CENTER { x: 1, y: 2 }
+- &LEFT { x: 0, y: 2 }
+- &BIG { r: 10 }
+- &SMALL { r: 1 }
+
+# All the following maps are equal:
+
+- # Override
+  << : [ *BIG, *LEFT, *SMALL ]
+  x: 1
+  label: center/big
+      eoyaml
+
+      hash = {
+        'x' => 1,
+        'y' => 2,
+        'r' => 10,
+        'label' => 'center/big'
+      }
+
+      assert_equal hash, Psych.load(yaml)[4]
+    end
+  end
+end
diff --git a/version.h b/version.h
index 514ab3e39f..4a6cf339b9 100644
--- a/version.h
+++ b/version.h
@@ -1,5 +1,5 @@
 #define RUBY_VERSION "1.9.2"
-#define RUBY_PATCHLEVEL 270
+#define RUBY_PATCHLEVEL 271
 #define RUBY_VERSION_MAJOR 1
 #define RUBY_VERSION_MINOR 9
 #define RUBY_VERSION_TEENY 1